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Let's Build a 28-Core Raspberry Pi Cluster

ikarus.sg

101–110 of 158 posts

Re: Let's Build a 28-Core Raspberry Pi Cluster

#101
post #96

Earlier quoted context omitted.

Hey there. Thanks for the article! I wanted to ask you if it is worth it implementing something similar in the cloud to learn kubernetes. The hardware is prohibitively expensive on Brazil, so maybe a cluster of t2.micro on AWS running for the total amount of 750 hours could serve the learning purpose for free

I don't know how it is in Brazil but in Europe and the US offices frequently go out of business that have dozens if not hundreds tiny desktop computers in their bankruptcy auctions. They've got i5 cpu's 4-8gb of ram and 128gb SSD's and go for (much) less than a hundred bucks. Stack 3 of them and you have a kubernetes cluster that you could carry in one hand and I think outperforms the 7 raspberry Pi 3's. Servethehome…

I think it’s lease companies replacing paid off business PCs. They rent boxes to offices on multi year contracts, collect and recycle them when the term is up.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#102
post #79

"This build is for you if you:" ahem, for 600 dollars I get a fine computer which can host all the kubernets and docker I ever want in a nice formfactor... I mean, it's cool and all, but effectively utterly useless except for the blinking lights.

Very cool work! I wonder the same, for a 'cluster' I'm expecting performance and large memory for example for scientific computing. Other than that I couldn't think of any other use cases. If anyone could enlighten me? Cheers

I made a cluster of 9 pi's for a work project, not for the computing power but for the segmentation. I had 8 pieces of equipment that needed to be monitored while undergoing various physical tests. A simple app was developed that would run on each piece being tested and communicate over the ethernet port each millisecond back to a pi, which then forwarded the on/off status to a central pc connected to the 9th pi acting as a wifi access point. This computer served as the monitor/display and logger of the system so we could see at a glance if everything was green and reporting or not.

It was important that each piece be physically isolated so that we knew the whole path was operational and nothing was short circuiting via something else's network connection. You could have accomplished something similar with VLANs and some routes, but this allowed for easier troubleshooting and to explain to the powers that be how things were guaranteed isolated because they could see it. Plus it looked cool.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#103
post #94

Earlier quoted context omitted.

Ahhh. I guess it depends on what you're looking for. Mellanox cards and related cabling is generally still pretty good (in UK and Australia anyway). A few years ago I obtained a few 24 port HP Procurve switches (3400cl-24G), with 10GbE (CX4 connectors) on the back. Those worked pretty well, though turned out to be slightly too noisy for use as desktop switches. ;) Taking a quick look on US Ebay now, something like th…

To help with the noise try replacing the fans with high quality ones. I threw some nocturnas into an old managed dell switch and it quieted down immensely. Just be aware that sometimes they change the pins around from the standard pinout, I blew out one of the fans before discovering this. Fan still works, just lost the rpm monitoring :(

Server fans are not cheap, they’re smaller and faster. Look at current and CFM rating. They might look insane from DIY market figures.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#104
post #79

"This build is for you if you:" ahem, for 600 dollars I get a fine computer which can host all the kubernets and docker I ever want in a nice formfactor... I mean, it's cool and all, but effectively utterly useless except for the blinking lights.

Depends what you're going for. I did a pi zero cluster a couple years back and it was an absolutely fantastic learning experience for me. There was something about it being tangible that helped keep me interested and force me to actually get it running. Also, the memory limitations, for example, made for a cool problem in setting up Hadoop on it.

It can totally be worth it to do something suboptimal, if it leads to a better learning path :)

Re: Let's Build a 28-Core Raspberry Pi Cluster

#105
post #20
post #4

Neat setup. An alternative would perhaps be a Pine64 Clusterboard with 7 SOPINE modules: https://store.pine64.org/product/clusterboard-with-7-sopine-...

I cannot recommend doing business with pine64, their customer service is nonexistent. If you cancel your order, or need to get ahold of someone @ sales@pine64.org for any exception, in my experience you may as well shout at the nearest wall. - Someone out $165 spent on a cancelled pinephone order, no phone and no refund, complete radio silence.

That's very unfortunate. I own 3 Pine64 products myself, my experience with their customer support has been great so far.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#106
post #4

Neat setup. An alternative would perhaps be a Pine64 Clusterboard with 7 SOPINE modules: https://store.pine64.org/product/clusterboard-with-7-sopine-...

I've been a bit curious about this and other multi-board CoM carrier boards like Turing Pi[0]. Have you used it and what's your experience? Like the author mentions, pre-4 Raspberry Pis gives sad throughput due to the shared bus; Rpi 4 would be much more suitable. There's also Odroid C4, Rockpi 4, Nanopi M4V2. [0]: https://www.jeffgeerling.com/blog/2020/raspberry-pi-cluster-...

No practical experience with any of these "cluster boards" yet, I'm afraid.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#107
post #94

Earlier quoted context omitted.

Ahhh. I guess it depends on what you're looking for. Mellanox cards and related cabling is generally still pretty good (in UK and Australia anyway). A few years ago I obtained a few 24 port HP Procurve switches (3400cl-24G), with 10GbE (CX4 connectors) on the back. Those worked pretty well, though turned out to be slightly too noisy for use as desktop switches. ;) Taking a quick look on US Ebay now, something like th…

To help with the noise try replacing the fans with high quality ones. I threw some nocturnas into an old managed dell switch and it quieted down immensely. Just be aware that sometimes they change the pins around from the standard pinout, I blew out one of the fans before discovering this. Fan still works, just lost the rpm monitoring :(

Thanks, very much agree.

I took a naive approach to it before having any clue about electronics, just replacing one of the (3) internal fans with a quieter one of the same voltage. Mostly to see if that would work.

While it functioned, the "fan warning" light was then permanently on (with the replacement fan in).

If I still had the gear and were to do it again, I'd investigate properly and figure out a real solution. :)

Re: Let's Build a 28-Core Raspberry Pi Cluster

#108
How timely... just today I received my CloverPi which I backed on Kickstarter (no other affiliation), a “back panel to enable 4 RaspberryPis to be clustered”.

Finally I can earn my “My other computer is a Beowulf Cluster” bumper sticker from what feels like aeons ago (courtesy of the now-defunct ThinkGeek.com).

Re: Let's Build a 28-Core Raspberry Pi Cluster

#109
post #66

Reminds me of moot "revealing" the "datacenter" that hosted 4chan: https://imgur.com/sBLRuZY I'm putting the air-quotes because I still sincerely hope that it was a joke

I'm more impressed he got trips, that's pretty amusing about the USB being as fast as an SSD. Technically SSD's are supposed to be based off SD card tech if I'm not mistaken, issue with a USB being based off the same tech is the USB speeds themselves vs a SSD can go significantly faster due to its connector (SATA or otherwise). Although I can see USB C being 'fast enough' instead.

Re: Let's Build a 28-Core Raspberry Pi Cluster

#110
post #66

Reminds me of moot "revealing" the "datacenter" that hosted 4chan: https://imgur.com/sBLRuZY I'm putting the air-quotes because I still sincerely hope that it was a joke

I'm more impressed he got trips, that's pretty amusing about the USB being as fast as an SSD. Technically SSD's are supposed to be based off SD card tech if I'm not mistaken, issue with a USB being based off the same tech is the USB speeds themselves vs a SSD can go significantly faster due to its connector (SATA or otherwise). Although I can see USB C being 'fast enough' instead.

>I'm more impressed he got trips

There's probably admin tools for that.

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